Xavier See, Dating Coach, Author of alife2love.com says:

On the flip-side, there is also a real possibility of success. If both of you have decided to try and make it work, I think you are off to as good a start as you can get because you already possess the most important factor needed for relationships to work : the will to stay together. All relationships, long-distance or not, will only work if both couples make a commitment to uphold their decision to stay together. As such, focus on doing things that will remind one another why both of you chose to stay together.

Having been in a long-distance relationship before and succeeding in maintaining it, here are 3 things which helped me keep my relationship together:

1) Communication

Like all relationships, communication is key. Both of you should work out a feasible communication routine that is sensitive to time differences and new schedules. Be sure to be realistic with both your expectations of each other, the last thing you want is to accuse one another of not trying hard enough when it was all either of you could afford. Generally, I would say that at least 3 times a week, make it a point to commit towards having a quality conversation through the phone or webcam. Be sure to sprinkle in a few thoughtful texts and e-mails from time to time for an added dash of surprise.
 
2) "Physical" Contact

Flying yourself over occasionally would be the best thing to do. However, if that is not within your means, sending physical gifts/letters is a viable alternative. Like in normal relationships, receiving a hand-written letter or handmade card means a lot more than an e-mail. The effect is multiplied when you receive these gifts when both of you are miles apart. If you know your partner's address, you can go to an online store in his city and order him something physical too. An ex-girlfriend of mine ordered me a pizza for dinner after I mentioned in the morning that I was going to stay in to webcam with her at night. I'll never forget that!

3) Social Ties

Maintaining and strengthening social ties with members of his family or his friends will pay off handsomely for you. When a Man's family or best friends are talking about you and reminding him how awesome his girlfriend in Singapore is, he will really take it to heart.